Structure-electromagnetic coupling innovative design and practice of ultrahigh-speed permanent magnet motor driven centrifugal hydrogen circulating pump

Abstract

The invention relates to the technical field of ultra-high-speed motor design, fluid mechanical engineering and electromagnetic-structure coupling, in particular to an innovative structure-electromagnetic coupling design of a centrifugal hydrogen circulating pump driven by an ultra-high-speed permanent magnet motor. The integrated coupling rotor system is formed by rigidly connecting a permanent magnet motor rotor and a centrifugal impeller through conical surface interference and key groove positioning, a rotor iron core is formed by laminating 0.2 mm ultrathin silicon steel sheets (35W250), and impeller blade molded lines are optimized based on electromagnetic force harmonic characteristics (the number of blades is equal to the number of motor poles + / -1); the coupling matching degree is remarkably improved: through structure-electromagnetic parameter collaborative optimization, the comprehensive efficiency of the system reaches 85% or above, and is improved by 12%-15% compared with that of a separation design; an anti-resonance damping module is combined with a frequency avoidance design, and the vibration acceleration in an ultra-high-speed interval is smaller than or equal to 8 g and is reduced by 60% or above compared with a traditional design; the torque-load matching time is less than or equal to 0.3 s when the flow is suddenly changed, overcurrent impact or surge is avoided, and the dynamic requirement of a fuel cell system is met.

Description

Technical Field

[0001] This application relates to the fields of ultra-high speed motor design, fluid machinery engineering, and electromagnetic-structure coupling technology, specifically an innovative structural-electromagnetic coupling design and its practical method for an ultra-high speed permanent magnet motor-driven centrifugal hydrogen circulation pump. Background Technology

[0002] Driven by the global goal of "dual carbon" energy, hydrogen energy, as a core carrier of zero-carbon energy, has seen explosive growth in key equipment technologies across its industrial chain. Centrifugal hydrogen circulation pumps driven by ultra-high-speed permanent magnet motors serve as the "heart" of fuel cell systems and hydrogen storage and transportation equipment, responsible for hydrogen pressurization, circulation, and flow regulation; their performance directly determines system efficiency and safety. This equipment needs to operate stably under combined conditions of ultra-high speed (100,000-250,000 r / min), strong electromagnetic force (1-2T magnetic field strength), and hydrogen corrosion (partial pressure 0.1-3 MPa). The synergistic matching of structural design and electromagnetic characteristics has become a technological bottleneck.

[0003] In existing technologies, the design of ultra-high-speed permanent magnet motors and centrifugal hydrogen circulation pumps generally adopts a "structure-electromagnetic separation optimization" model: first, the structural parameters of the impeller, pump body, etc., are determined based on fluid dynamics simulation (such as the patent CN115260878A which focuses on impeller aerodynamic optimization); then, the electromagnetic scheme is designed based on motor theory (such as the patent CN114849253A which optimizes the permanent magnet arrangement); and finally, they are combined through simple mechanical connections. This model leads to a "parameter matching blind spot" between the two under dynamic operating conditions: for example, the rotor vibration caused by the impeller aerodynamic load is coupled with the harmonics of the motor's electromagnetic force, which easily causes resonance at speeds above 150,000 r / min; the nonlinear change of the motor's electromagnetic loss with increasing speed lacks coordinated control with the speed sensitivity of the pump's hydraulic efficiency, resulting in a 10%-15% decrease in the overall system efficiency.

[0004] The core shortcomings of existing technologies include: lack of coupling mechanism: structural parameters (such as impeller mass distribution and rotor stiffness) and electromagnetic parameters (such as air gap magnetic field density and winding current frequency) are designed independently without considering the dynamic coupling effect between the two. Under ultra-high speed, rotor instability is easily caused by the superposition of "electromagnetic force-centrifugal force-aerodynamic load"; prominent resonance risk: traditional design has not established a matching model between the structure's natural frequency and electromagnetic harmonic frequency. When the motor speed approaches the rotor's first-order critical speed (180,000-200,000 r / min), electromagnetic harmonics are prone to excite resonance, and the vibration acceleration can reach more than 20g; and lag in dynamic response: when the hydrogen flow rate fluctuates (0.5-5 kg / h), the matching delay between the motor output torque and the pump load is >0.5s, which easily leads to "overcurrent impact" or "stall surge".

[0005] Insufficient multi-physics field coordination: The heat dissipation design is separated from the heat generated by electromagnetic loss (accounting for 60% of the total heat) and the heat generated by fluid friction in the pump body (accounting for 40%), resulting in a local temperature difference >30℃, which aggravates the demagnetization of permanent magnets and thermal deformation of the structure. Summary of the Invention

[0006] This application provides an innovative design and practice method for the structural-electromagnetic coupling of an ultra-high-speed permanent magnet motor driven centrifugal hydrogen circulation pump. By constructing an innovative three-in-one system of "parameter collaborative optimization, dynamic coupling control, and multi-field collaborative regulation", it solves the problems of insufficient structural-electromagnetic coupling, high resonance risk, and lag in dynamic response in the existing technology, and achieves efficient and stable operation under ultra-high-speed conditions.

[0007] To achieve the above objectives, this application provides the following technical solution: an innovative structural-electromagnetic coupling design for an ultra-high-speed permanent magnet motor-driven centrifugal hydrogen circulation pump, including...

[0008] Integrated coupled rotor system: It consists of a permanent magnet motor rotor and a centrifugal impeller rigidly connected by "conical interference + keyway positioning". The rotor core is made of 0.2mm ultra-thin silicon steel sheets (35W250) stacked together. The impeller blade profile is optimized based on electromagnetic force harmonic characteristics (number of blades = number of motor poles ±1).

[0009] Electromagnetic-structural co-controller: It has a built-in coupling parameter mapping model and is electrically connected to the rotor vibration sensor (10-5000Hz), air gap magnetic field sensor (accuracy ±1mT), and hydrogen flow sensor (range 0.1-5kg / h) respectively. It can correct the motor current frequency and impeller inlet guide vane opening in real time.

[0010] Multi-field coordinated cooling system: includes a spiral water cooling jacket (flow rate 2-8L / min) surrounding the motor stator and an air-cooled channel in the pump body jacket (air velocity 10-20m / s), and the two achieve dynamic heat distribution through an electromagnetic proportional valve (adjusted according to the temperature difference ΔT between the motor and the pump body);

[0011] Anti-resonance damping module: Magnetorheological dampers are installed at both ends of the rotor. The damping coefficient can be adjusted in real time (0.1-1.0 N·s / m) by the coordinating controller to suppress resonant vibration.

[0012] Among them: the rotational inertia matching coefficient (motor rotor inertia / impeller inertia) of the integrated rotor is controlled at 1.2-1.5, and the air gap length (0.3-0.5mm) is dynamically compensated with the rotor radial deformation (≤0.02mm); the core algorithm of the electromagnetic-structure cooperative controller is a coupling parameter optimization model based on improved particle swarm optimization (iteration accuracy ≤0.1%).

[0013] Preferably, the permanent magnets of the integrated coupled rotor system adopt a “V-shaped alternating arrangement + segmented structure”, with each pole magnet divided into 3 segments (each segment arc length ratio 1:1.2:1), a pole arc coefficient of 0.72-0.78, a neodymium iron boron magnet grade of 42SH (remanence ≥1.32T, coercivity ≥2000kA / m), and a rotor sheath made of TC11 titanium alloy (beta heat treated, hardness 38-42HRC).

[0014] Preferably, the centrifugal impeller has an inlet angle of 18°-22°, an outlet angle of 30°-35°, and 7 blades (matching an 8-pole motor design). The blade profile is fitted with NURBS curves and optimized through electromagnetic force harmonic excitation simulation to ensure that the blade's natural frequency avoids the main harmonic frequency of electromagnetic force (2000-3000Hz).

[0015] Preferably, the coupling parameter mapping model of the electromagnetic-structure cooperative controller includes:

[0016] Electromagnetic-mechanical mapping unit: Establish the relationship between air gap magnetic field strength (B) and rotor radial force (F): F=k·B 2 • D (k is the structural coefficient, D is the rotor diameter), automatically reduces the motor current by 10%-15% when F≥500N;

[0017] Rotation speed-vibration mapping unit: Based on the curve of rotor vibration acceleration (a) and rotation speed (n), when a≥15g and n is close to the first-order critical speed (190000r / min), the magnetorheological damper is triggered to enhance damping (the coefficient is increased to 0.8-1.0N·s / m).

[0018] Preferably, the spiral water-cooled jacket of the multi-field synergistic cooling system has a semi-circular cross-section (8-10mm in diameter) and the coolant is a 50% ethylene glycol aqueous solution; the pump body jacket air-cooled channel adopts a diffuser design (inlet air velocity 10m / s, outlet air velocity 20m / s), and the flow distribution ratio of the two is dynamically adjusted with ΔT: when ΔT≥25℃, water cooling accounts for 70%; when ΔT≤10℃, air cooling accounts for 60%.

[0019] Preferably, the magnetic field strength of the magnetorheological damper is adjusted by the co-controller through the excitation coil current (0-2A), with a response time ≤50ms, and the vibration acceleration can be attenuated to below 5g at the resonance frequency point (190000r / min).

[0020] Preferably, the dynamic response module of the electromagnetic-structure coordinated controller can achieve torque-load matching when the hydrogen flow rate changes abruptly (0.5→3kg / h), with an adjustment time ≤0.3s and overshoot ≤5%.

[0021] A structural-electromagnetic coupling practical method for an ultra-high-speed permanent magnet motor-driven centrifugal hydrogen circulation pump includes the following steps.

[0022] S1: Initialization of coupling parameters: Based on the design target (speed 200000 r / min, flow rate 2 kg / h), the initial parameters (polar arc coefficient 0.75, number of blades 7, air gap 0.4 mm) are loaded through the cooperative controller;

[0023] S2: Dynamic coupling debugging: Start the equipment and collect vibration, magnetic field and flow signals in real time. Optimize the current frequency (20-50kHz) and guide vane opening (20%-80%) through the coupling model.

[0024] S3: Resonance suppression verification: A frequency sweep test was performed in the range of 180,000-200,000 r / min, triggering the adjustment of the magnetorheological damper, and the vibration attenuation effect was recorded.

[0025] S4: Multi-field collaborative optimization: Adjust the flow distribution of the cooling system according to the temperature difference between the motor (≤120℃) and the pump body (≤80℃), and verify the performance by running stably for 1000 hours.

[0026] Preferably, the current frequency adjustment in the dynamic coupling debugging in S2 adopts the "harmonic injection method", which injects 3% of the fifth harmonic into the fundamental current to cancel the third harmonic component of the impeller aerodynamic load and reduce vibration by 15%-20%.

[0027] Preferably, the performance verification indicators for multi-field collaborative optimization in S4 include: overall system efficiency ≥ 85%, vibration acceleration ≤ 8g, and hydrogen leakage rate ≤ 1×10⁻⁶. -7 Pa·m 3 / s, after 1000 hours of continuous operation, the magnetic performance of the permanent magnet decreases by ≤3%.

[0028] Compared with the prior art, the beneficial effects of this application are:

[0029] Significantly improved coupling matching: Through the coordinated optimization of structural and electromagnetic parameters, the overall system efficiency reaches over 85%, which is 12%-15% higher than that of separate design;

[0030] Resonance risk is controllable: The anti-resonance damping module is combined with the frequency avoidance design, and the vibration acceleration in the ultra-high speed range is ≤8g, which is more than 60% lower than that of traditional designs;

[0031] Rapid dynamic response: Torque-load matching time ≤0.3s during sudden flow changes, without overcurrent shock or surge, adapting to the dynamic requirements of fuel cell systems;

[0032] Multi-field coordinated stability: The cooling system dynamically distributes heat, the temperature difference between the motor and the pump body is ≤20℃, the attenuation rate of the permanent magnet is ≤3% after 1000h, and the structural thermal deformation is ≤0.01mm. Attached Figure Description

[0033] Figure 1 This is a flowchart of the application process. Detailed Implementation

[0034] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0035] Please see Figure 1 This application provides the following technical solution: an innovative structural-electromagnetic coupling design for an ultra-high-speed permanent magnet motor-driven centrifugal hydrogen circulation pump, including...

[0036] Integrated coupled rotor system: It consists of a permanent magnet motor rotor and a centrifugal impeller rigidly connected by "conical interference + keyway positioning". The rotor core is made of 0.2mm ultra-thin silicon steel sheets (35W250) stacked together. The impeller blade profile is optimized based on electromagnetic force harmonic characteristics (number of blades = number of motor poles ±1).

[0037] Electromagnetic-structural co-controller: It has a built-in coupling parameter mapping model and is electrically connected to the rotor vibration sensor (10-5000Hz), air gap magnetic field sensor (accuracy ±1mT), and hydrogen flow sensor (range 0.1-5kg / h) respectively. It can correct the motor current frequency and impeller inlet guide vane opening in real time.

[0038] Multi-field coordinated cooling system: includes a spiral water cooling jacket (flow rate 2-8L / min) surrounding the motor stator and an air-cooled channel in the pump body jacket (air velocity 10-20m / s), and the two achieve dynamic heat distribution through an electromagnetic proportional valve (adjusted according to the temperature difference ΔT between the motor and the pump body);

[0039] Anti-resonance damping module: Magnetorheological dampers are installed at both ends of the rotor. The damping coefficient can be adjusted in real time (0.1-1.0 N·s / m) by the coordinating controller to suppress resonant vibration.

[0040] Among them: the rotational inertia matching coefficient (motor rotor inertia / impeller inertia) of the integrated rotor is controlled at 1.2-1.5, and the air gap length (0.3-0.5mm) is dynamically compensated with the rotor radial deformation (≤0.02mm); the core algorithm of the electromagnetic-structure cooperative controller is a coupling parameter optimization model based on improved particle swarm optimization (iteration accuracy ≤0.1%).

[0041] Preferably, the permanent magnets of the integrated coupled rotor system adopt a “V-shaped alternating arrangement + segmented structure”, with each pole magnet divided into 3 segments (each segment arc length ratio 1:1.2:1), a pole arc coefficient of 0.72-0.78, a neodymium iron boron magnet grade of 42SH (remanence ≥1.32T, coercivity ≥2000kA / m), and a rotor sheath made of TC11 titanium alloy (beta heat treated, hardness 38-42HRC).

[0042] Preferably, the centrifugal impeller has an inlet angle of 18°-22°, an outlet angle of 30°-35°, and 7 blades (matching an 8-pole motor design). The blade profile is fitted with NURBS curves and optimized through electromagnetic force harmonic excitation simulation to ensure that the blade's natural frequency avoids the main harmonic frequency of electromagnetic force (2000-3000Hz).

[0043] Preferably, the coupling parameter mapping model of the electromagnetic-structure cooperative controller includes:

[0044] Electromagnetic-mechanical mapping unit: Establish the relationship between air gap magnetic field strength (B) and rotor radial force (F): F=k·B 2 • D (k is the structural coefficient, D is the rotor diameter), automatically reduces the motor current by 10%-15% when F≥500N;

[0045] Rotation speed-vibration mapping unit: Based on the curve of rotor vibration acceleration (a) and rotation speed (n), when a≥15g and n is close to the first-order critical speed (190000r / min), the magnetorheological damper is triggered to enhance damping (the coefficient is increased to 0.8-1.0N·s / m).

[0046] Preferably, the spiral water-cooled jacket of the multi-field synergistic cooling system has a semi-circular cross-section (8-10mm in diameter) and the coolant is a 50% ethylene glycol aqueous solution; the pump body jacket air-cooled channel adopts a diffuser design (inlet air velocity 10m / s, outlet air velocity 20m / s), and the flow distribution ratio of the two is dynamically adjusted with ΔT: when ΔT≥25℃, water cooling accounts for 70%; when ΔT≤10℃, air cooling accounts for 60%.

[0047] Preferably, the magnetic field strength of the magnetorheological damper is adjusted by the co-controller through the excitation coil current (0-2A), with a response time ≤50ms, and the vibration acceleration can be attenuated to below 5g at the resonance frequency point (190000r / min).

[0048] Preferably, the dynamic response module of the electromagnetic-structure coordinated controller can achieve torque-load matching when the hydrogen flow rate changes abruptly (0.5→3kg / h), with an adjustment time ≤0.3s and overshoot ≤5%.

[0049] A structural-electromagnetic coupling practical method for an ultra-high-speed permanent magnet motor-driven centrifugal hydrogen circulation pump includes the following steps.

[0050] S1: Initialization of coupling parameters: Based on the design target (speed 200000 r / min, flow rate 2 kg / h), the initial parameters (polar arc coefficient 0.75, number of blades 7, air gap 0.4 mm) are loaded through the cooperative controller;

[0051] S2: Dynamic coupling debugging: Start the equipment and collect vibration, magnetic field and flow signals in real time. Optimize the current frequency (20-50kHz) and guide vane opening (20%-80%) through the coupling model.

[0052] S3: Resonance suppression verification: A frequency sweep test was performed in the range of 180,000-200,000 r / min, triggering the adjustment of the magnetorheological damper, and the vibration attenuation effect was recorded.

[0053] S4: Multi-field collaborative optimization: Adjust the flow distribution of the cooling system according to the temperature difference between the motor (≤120℃) and the pump body (≤80℃), and verify the performance by running stably for 1000 hours.

[0054] Preferably, the current frequency adjustment in the dynamic coupling debugging in S2 adopts the "harmonic injection method", which injects 3% of the fifth harmonic into the fundamental current to cancel the third harmonic component of the impeller aerodynamic load and reduce vibration by 15%-20%.

[0055] Preferably, the performance verification indicators for multi-field collaborative optimization in S4 include: overall system efficiency ≥ 85%, vibration acceleration ≤ 8g, and hydrogen leakage rate ≤ 1×10⁻⁶. -7 Pa·m 3 / s, after 1000 hours of continuous operation, the magnetic performance of the permanent magnet decreases by ≤3%.

[0056] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An innovative structural-electromagnetic coupling design for a centrifugal hydrogen circulation pump driven by an ultra-high-speed permanent magnet motor, characterized by: include Integrated coupled rotor system: It consists of a permanent magnet motor rotor and a centrifugal impeller rigidly connected by "conical interference + keyway positioning". The rotor core is made of 0.2mm ultra-thin silicon steel sheets (35W250) stacked together. The impeller blade profile is optimized based on electromagnetic force harmonic characteristics (number of blades = number of motor poles ±1). Electromagnetic-structural co-controller: It has a built-in coupling parameter mapping model and is electrically connected to the rotor vibration sensor (10-5000Hz), air gap magnetic field sensor (accuracy ±1mT), and hydrogen flow sensor (range 0.1-5kg / h) respectively. It can correct the motor current frequency and impeller inlet guide vane opening in real time. Multi-field coordinated cooling system: includes a spiral water cooling jacket (flow rate 2-8L / min) surrounding the motor stator and an air-cooled channel in the pump body jacket (air velocity 10-20m / s), and the two achieve dynamic heat distribution through an electromagnetic proportional valve (adjusted according to the temperature difference ΔT between the motor and the pump body); Anti-resonance damping module: Magnetorheological dampers are installed at both ends of the rotor. The damping coefficient can be adjusted in real time (0.1-1.0 N·s / m) by the coordinating controller to suppress resonant vibration. Among them: the rotational inertia matching coefficient (motor rotor inertia / impeller inertia) of the integrated rotor is controlled at 1.2-1.5, and the air gap length (0.3-0.5mm) is dynamically compensated with the rotor radial deformation (≤0.02mm); the core algorithm of the electromagnetic-structure cooperative controller is a coupling parameter optimization model based on improved particle swarm optimization (iteration accuracy ≤0.1%).

2. The design according to claim 1, characterized in that: The permanent magnets of the integrated coupled rotor system adopt a "V-shaped alternating arrangement + segmented structure". Each pole magnet is divided into 3 segments (each segment arc length ratio 1:1.2:1), the pole arc coefficient is 0.72-0.78, the neodymium iron boron magnet grade is 42SH (remanence ≥1.32T, coercivity ≥2000kA / m), and the rotor sheath is made of TC11 titanium alloy (beta heat treated, hardness 38-42HRC).

3. The design according to claim 1, characterized in that: The centrifugal impeller has an inlet angle of 18°-22° and an outlet angle of 30°-35°, with 7 blades (matching an 8-pole motor design). The blade profile is fitted with NURBS curves and optimized through electromagnetic force harmonic excitation simulation to ensure that the blade's natural frequency avoids the main harmonic frequencies of electromagnetic force (2000-3000Hz).

4. The design according to claim 1, characterized in that: The coupling parameter mapping model of the electromagnetic-structure cooperative controller includes: Electromagnetic-mechanical mapping unit: Establish the relationship between air gap magnetic field strength (B) and rotor radial force (F): F=k·B 2 • D (k is the structural coefficient, D is the rotor diameter), automatically reduces the motor current by 10%-15% when F≥500N; Rotation speed-vibration mapping unit: Based on the curve of rotor vibration acceleration (a) and rotation speed (n), when a≥15g and n is close to the first-order critical speed (190000r / min), the magnetorheological damper is triggered to enhance damping (the coefficient is increased to 0.8-1.0N·s / m).

5. The design according to claim 1, characterized in that: The spiral water-cooled jacket of the multi-field synergistic cooling system has a semi-circular cross-section (8-10mm in diameter) and uses a 50% ethylene glycol aqueous solution as the coolant. The pump body jacket air-cooled channel adopts a diffuser design (inlet air velocity 10m / s, outlet air velocity 20m / s), and the flow distribution ratio of the two is dynamically adjusted with ΔT: when ΔT≥25℃, water cooling accounts for 70%; when ΔT≤10℃, air cooling accounts for 60%.

6. The design according to claim 1, characterized in that: The magnetic field strength of the magnetorheological damper is adjusted by the co-controller through the excitation coil current (0-2A), with a response time ≤50ms. At the resonance frequency point (190000r / min), the vibration acceleration can be attenuated to below 5g.

7. The design according to claim 1, characterized in that: The dynamic response module of the electromagnetic-structure co-controller can achieve torque-load matching when hydrogen flow rate changes abruptly (0.5→3kg / h), with a settling time ≤0.3s and overshoot ≤5%.

8. A structural-electromagnetic coupling method for an ultra-high-speed permanent magnet motor-driven centrifugal hydrogen circulation pump, characterized in that: Includes the following steps S1: Initialization of coupling parameters: Based on the design target (speed 200000 r / min, flow rate 2 kg / h), the initial parameters (polar arc coefficient 0.75, number of blades 7, air gap 0.4 mm) are loaded through the cooperative controller; S2: Dynamic coupling debugging: Start the equipment and collect vibration, magnetic field and flow signals in real time. Optimize the current frequency (20-50kHz) and guide vane opening (20%-80%) through the coupling model. S3: Resonance suppression verification: A frequency sweep test was performed in the range of 180,000-200,000 r / min, triggering the adjustment of the magnetorheological damper, and the vibration attenuation effect was recorded. S4: Multi-field collaborative optimization: Adjust the flow distribution of the cooling system according to the temperature difference between the motor (≤120℃) and the pump body (≤80℃), and verify the performance by running stably for 1000 hours.

9. The method according to claim 8, characterized in that: The current frequency adjustment in the dynamic coupling debugging of S2 adopts the "harmonic injection method", which injects 3% of the fifth harmonic into the fundamental current to cancel the third harmonic component of the impeller aerodynamic load and reduce vibration by 15%-20%.

10. The method according to claim 8, characterized in that: The performance verification metrics for multi-field collaborative optimization in S4 include: overall system efficiency ≥ 85%, vibration acceleration ≤ 8g, and hydrogen leakage rate ≤ 1×10⁻⁶. 7 Pa·m 3 / s, after 1000 hours of continuous operation, the magnetic performance of the permanent magnet decreases by ≤3%.

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